[MacPorts] #59837: macOS 10.14 SDK does not appear to be installed even though Command Line Tools are installed

[MacPorts]

#59837: macOS 10.14 SDK does not appear to be installed even though Command Line
Tools are installed
------------------------+--------------------
  Reporter:  manulcaux  |      Owner:  (none)
      Type:  defect     |     Status:  new
  Priority:  Normal     |  Milestone:
 Component:  base       |    Version:
Resolution:             |   Keywords:
      Port:             |
------------------------+--------------------

Comment (by kencu):

 I believe you have the current xcode installed (with SDK 10.15), and the
 CLI tools from the last version that came with SDK 10.14. That situation
 is unworkable, as you have mismatched tools.

 Here is what I would do, exactly.

 1. Save the 10.14 SDK you already have:
 {{{
 sudo mkdir /Library/Developer/SavedSDKS
 sudo mv    /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk
 /Library/Developer/SavedSDKS/MacOSX10.14.sdk
 }}}

 2. Remove the outdated CLTs:
 {{{
 sudo rm -rf /Library/Developer/CommandLineTools
 }}}

 3. Install the current CLTs using the current CLT installer.

 4. Add a symlink for the MacOSX10.14.sdk into the current CLTs:
 {{{
 sudo ln -s /Library/Developer/SavedSDKS/MacOSX10.14.sdk
 /Library/Developer/CommandLineTools/SDKs/MacOSX10.14.sdk
 }}}

 5. Add a symlink for the MacOSX10.14.sdk into Xcode:
 {{{
 sudo ln -s /Library/Developer/SavedSDKS/MacOSX10.14.sdk
 /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.14.sdk
 }}}

 Then I believe you should be in business.

-- 
Ticket URL: <https://trac.macports.org/ticket/59837#comment:17>
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